French Lake
French Lake in Hennepin County, Minnesota has a water quality grade of D (Nutrient-rich). Water clarity: 3 ft visibility. Phosphorus: 50.2 µg/L.
- Clarity
- 3 ft
- Typical in August
- 70°F
- Max depth
- ~38 ft est.
- Type
- Eutrophic
- Public access
- Yes
Grade D measures nutrients and algae, not whether this is a good place for a cabin trip. Cabins and rentals near French Lake →
Next lake in Hennepin County
French Lake is a productive, nutrient-rich eutrophic lake in Hennepin County, Minnesota with an estimated average depth of about 38 feet. Water quality is graded D based on 2 sampling years through 2024. Limited fish-species data available. Public access is available with 1 public boat landing. Compared to the 80 other monitored lakes in Hennepin County, French Lake ranks #46 for water quality.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, last sampled 2024-10-01. Grade methodology: LakeGrade methodology.
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Swimming Safety
Grade onlyLimited data
Based on clarity and algae grades from past sampling — we do not hold live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
Nutrients and algae run higher than average — check local advisories before swimming, and skip the water if you see scum
Water Quality Grade: D (Nutrient-rich)
Very murky, less than 3 ft of visibility. Phosphorus level: 50.2 µg/L. Trophic State Index: 61.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 3 ft | Not graded |
| Phosphorus | 50.2 µg/L | Poor |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 61 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Where to stay near French Lake
Compare lakeside cabins, hotels, and vacation rentals near French Lake in Hennepin County, Minnesota — live availability and prices for your trip. Switch the map to Satellite to see the lake and how close each stay is to the water. The water-quality grade measures nutrients and algae, not lodging — cabins and rentals around French Lake are listed below.
Top-rated places to stay near French Lake
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Planning a whole trip? See where to stay at Minnesota’s top lakes →
Water Temperature
French Lake typically sits around 70°F at the surface in August. Summer average is about 71°F. Usually warmest in Jul (about 74°F) and coldest in Apr (about 44°F). These are typical values by month — not a live reading.
Typical surface water temperature by month, from 30 field readings (2010–2024) via the EPA Water Quality Portal. See the full French Lake water temperature breakdown →
Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | ~38 ft est. |
| Average Depth | ~10 ft est. |
| Public Access | Yes |
Depth marked “est.” is a modeled maximum from GLOBathy (Khazaei et al. 2022, CC0), not a measured survey. Minnesota has not published bathymetry for French Lake.
Lake Size & Watershed
Size, shoreline, and watershed area from HydroLAKES (HydroSHEDS). Mean depth here is modelled, not surveyed — HydroLAKES v1.0 estimates lake depth from surrounding terrain rather than from soundings. Treat it as an approximation, and prefer a state bathymetric survey where one exists.
Recreation & Access
- French LakePublic
Fishing French Lake
EPA Impairment Status
French Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 4A).
Causes of impairment
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit MN27-0125-00 · Official waterbody report · Matched by proximity (2.64 km)
Regulated Pollution Sources Nearby
1 EPA-permitted facility operate within about 5 miles of French Lake under Clean Water Act (NPDES) discharge permits.
- Dayton Mobile Home ParkOsseo · 1 mi away · NPDES MN0041432
Facilities permitted to discharge under the Clean Water Act within ~5 miles; proximity does not by itself mean a facility affects this lake. Source: EPA ECHO (ICIS-NPDES), as of 2026-07.
County Ranking
Ranked #46 of 81 lakes in Hennepin County
Nearby Lakes in Hennepin County
Frequently asked questions about French Lake
What is the water quality grade for French Lake?
- French Lake in Hennepin County, Minnesota has a water quality grade of D (Nutrient-rich). Water clarity: 3 ft visibility. Phosphorus: 50.2 µg/L.
Is French Lake safe to swim in?
- Nutrients and algae run higher than average — check local advisories before swimming, and skip the water if you see scum. French Lake has a water quality grade of D (Nutrient-rich). Always check local health department advisories before swimming.
What is the water temperature of French Lake?
- French Lake typically sits around 70°F at the surface in August, from 30 EPA Water Quality Portal field readings (2010–2024). That is a typical value for the month, not a live reading.
How deep is French Lake?
- No published bathymetric survey covers French Lake, so its depth has not been measured. The HydroLAKES global model estimates an average depth of about 38 feet, but that is a modelled estimate derived from surrounding terrain rather than a measurement on the water, so treat it as approximate.
Are there boat ramps on French Lake?
- French Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include French Lake. Public access is listed as yes.
Explore French Lake across LakeGrade
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Where this data comes from
18 measurements from 1 monitoring station, 2024. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Minnesota Pollution Control Agency - Ambient Surface Water
MNPCA18 samples · 2024
Analytical methods
- Field measurement/observation, generic method
- Phosphorus by Two Reagent Colorimetry
- 4500 N C ~ Persufate Method for Total Nitrogen
Monitoring station identifiers (1)
Grade thresholds from the EPA National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See how grades are calculated and data sources.
Other records on this page
Impairment status from EPA ATTAINS 303(d) database
Regulated discharger data from EPA ECHO (ICIS-NPDES)
Lake size & watershed from HydroLAKES (HydroSHEDS)
Lake details from Minnesota DNR LakeFinder
Named boat-access points from the USGS National Boat Ramps inventory